{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T17:46:23Z","timestamp":1785433583165,"version":"3.56.0"},"reference-count":38,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T00:00:00Z","timestamp":1783987200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001659","name":"Deutsche Forschungsgemeinschaft","doi-asserted-by":"publisher","award":["AL 1179\/4-1"],"award-info":[{"award-number":["AL 1179\/4-1"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001659","name":"Deutsche Forschungsgemeinschaft","doi-asserted-by":"publisher","award":["CI 263\/3-1"],"award-info":[{"award-number":["CI 263\/3-1"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]},{"award":["AL 1179\/4-1"],"award-info":[{"award-number":["AL 1179\/4-1"]}],"id":[{"id":"https:\/\/ror.org\/018mejw64","id-type":"ROR","asserted-by":"publisher"}]},{"award":["CI 263\/3-1"],"award-info":[{"award-number":["CI 263\/3-1"]}],"id":[{"id":"https:\/\/ror.org\/018mejw64","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Repeated exposure to subinhibitory concentrations of antiseptics may lead to reduced susceptibility or resistance and potentially promote cross-resistance to antibiotics. However, the underlying molecular mechanisms remain incompletely understood. This study investigated whether antiseptic-adapted Escherichia coli strains exhibit altered protein expression profiles compared with wild-type (WT) E. coli. Protein expression was analysed in E. coli strains previously adapted over ten passages to subinhibitory concentrations of chlorhexidine (CHX), cetylpyridinium chloride (CPC), and benzalkonium chloride (BAC). WT bacteria were exposed to sub-minimum inhibitory concentrations (sub-MICs) of antiseptics for 3 h to induce stress. Untreated WT and heat-shocked WT E. coli (42 \u00b0C, 2 h) served as controls. Protein expression profiles were assessed using SDS-PAGE and Western blotting targeting stress-associated proteins. SDS-PAGE demonstrated altered protein expression patterns in antiseptic-adapted strains, including differences in band intensities and additional protein bands. Western blot analysis showed increased DnaK and GroEL expression with reduced LexA levels in heat-shocked WT bacteria, whereas RecA remained largely unchanged. Antiseptic-adapted strains exhibited increased DnaK, GroEL, and OmpF expression together with reduced LexA and RecA expression. These findings indicate that adaptation to antiseptics involves complex mechanisms among multiple proteins rather than a single adaptive mechanism.<\/jats:p>","DOI":"10.3390\/microorganisms14071533","type":"journal-article","created":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T08:04:31Z","timestamp":1784016271000},"page":"1533","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Protein Expression Profiles of Antiseptic-Adapted Escherichia coli"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-8688-2886","authenticated-orcid":false,"given":"David L.","family":"Auer","sequence":"first","affiliation":[{"name":"Department of Operative Dentistry and Periodontology, Center for Dental Medicine, Medical Center & Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Uemmuehan","family":"Akyol","sequence":"additional","affiliation":[{"name":"Department of Conservative Dentistry and Periodontology, University Hospital Regensburg, 93053 Regensburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Denise","family":"Muehler","sequence":"additional","affiliation":[{"name":"Department of Conservative Dentistry and Periodontology, University Hospital Regensburg, 93053 Regensburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4450-4238","authenticated-orcid":false,"given":"Konstantin J.","family":"Scholz","sequence":"additional","affiliation":[{"name":"Department of Operative Dentistry and Periodontology, Center for Dental Medicine, Medical Center & Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4726-9555","authenticated-orcid":false,"given":"Karl-Anton","family":"Hiller","sequence":"additional","affiliation":[{"name":"Department of Operative Dentistry and Periodontology, Center for Dental Medicine, Medical Center & Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany"},{"name":"Department of Conservative Dentistry and Periodontology, University Hospital Regensburg, 93053 Regensburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tim","family":"Maisch","sequence":"additional","affiliation":[{"name":"Department of Dermatology, University Hospital Regensburg, 93053 Regensburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wolfgang","family":"Buchalla","sequence":"additional","affiliation":[{"name":"Department of Conservative Dentistry and Periodontology, University Hospital Regensburg, 93053 Regensburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8769-599X","authenticated-orcid":false,"given":"Ali","family":"Al-Ahmad","sequence":"additional","affiliation":[{"name":"Department of Operative Dentistry and Periodontology, Center for Dental Medicine, Medical Center & Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1750-7380","authenticated-orcid":false,"given":"Fabian","family":"Cieplik","sequence":"additional","affiliation":[{"name":"Department of Operative Dentistry and Periodontology, Center for Dental Medicine, Medical Center & Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1199","DOI":"10.1016\/S0140-6736(24)01867-1","article-title":"Global Burden of Bacterial Antimicrobial Resistance 1990\u20132021: A Systematic Analysis with Forecasts to 2050","volume":"404","author":"Naghavi","year":"2024","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"107786","DOI":"10.1016\/j.ijantimicag.2026.107786","article-title":"Global Burden of Antimicrobial Resistance in Lower Respiratory Infections: A Systematic Analysis for the Global Burden of Disease Study 2021","volume":"67","author":"Qin","year":"2026","journal-title":"Int. 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